The invention is directed to an apparatus for holding and dispensing metered amounts of at least one active composition into a washing machine, a laundry dryer or a dishwashing machine.
Already known from German published patent application DE 197 40 819 A1 is a metering and dispensing device inside a mechanism designed to add powdered detergent in doses to water-operated washing machines. The device is provided with two compartments disposed in one plane for receiving the powdered detergent, which is discharged into a processing container of the washing machine. The compartments have filling openings, through which any individual or all of the compartments can be selectively filled with the powdered detergent. The filling openings communicate with an outlet opening of a funnel-shaped detergent hopper mechanism and simultaneously serve as individually activatable openings for the purpose of dispensing to the rinsing or washing water, co-operating with synchronously controllable outlet openings for the water admixed with the powdered detergent. The individual doses of detergent are discharged by a manual setting operated by the user or by an operating program selected by the user.
U.S. Pat. No. 4,379,515 discloses a dispensing device for detergent, comprising a rigid container and, communicating with this rigid container by means of a pipe, a compressible reservoir containing the measured quantity of detergent needed for one washing cycle. Under the effect of centrifugal forces generated by rotation of the laundry drum, the reservoir is compressedxe2x80x94particularly if it is disposed between the laundry and the wall of the laundry drumxe2x80x94in such a way that its contents are emptied into the rigid container, where the detergent is then dissolved by the washing liquor. A disadvantage of this dispensing system resides in the fact that the reservoir can be used for only one respective washing cycle and has to be replaced with each new washing cycle.
European patent publication EP 0 215 366 describes a detergent container with a welded seal, wherein the welded seal melts at a specific operating temperature and then releases the detergent. The seal of the container in particular cannot be used again and, in addition, it is not possible to dispense more than once with this system.
European patent publication EP 0 328 769 describes a removable dispensing container with a closure that can be opened during a washing cycle and which has a manipulating extension. The pressure exerted by the laundry during the washing cycle causes the manipulating extension to be pushed into the dispensing container in such a way that the detergent is able to flow out. It is not possible to dispense more than one dose, and the dispensing container must be filled again before each washing cycle.
German patent publication DE 39 02 356 discloses a dispensing container which may be used for a single washing cycle only and operates on the basis of a temperature-dependent release of a liquid fabric conditioner. The rising temperature causes the pressure in the dispensing container to rise above atmospheric pressure, as a result of which a gate valve is displaced into its open position, permitting the liquid fabric conditioner to flow into the washing machine.
U.S. Pat. No. 5,033,643 describes a dispensing container, which also allows a metering unit to be released for only one washing cycle. Forces generated by the wet laundry act on the release mechanism of the dispensing container.
German patent publications DE 39 34 123 and DE 39 22 342 describe detergent containers which are fixedly mounted on the laundry drum. Pins or locking hooks are used for fixing purposes. With these containers, no provision is made for more than one dose, which means that they have to be removed from the washing machine after every washing cycle and re-filled.
U.S. Pat. No. 5,176,297 describes a dispensing system for a dishwasher, which is mounted in the interior of the machine and incorporates a supply and a dispensing compartment. Although it is possible to dispense more than one dose, the dispensing system is controlled by the dishwasher in a complex manner.
German patent publication DE 195 40 608 discloses a system enabling more than one dose to be dispensed, in which tablets of dishwasher detergent are placed. The individual doses are controlled by a command issued by the dishwasher, i.e. an operating program of the dishwasher selected by the user controls the time at which the dose is released.
Australian published patent application AU-A-78393/91 discloses a dispensing container for a detergent, which is dispensed through an orifice opened by the build-up of internal pressure in the container. This internal pressure is generated either by the operating program of the machine or by operation directly on the part of the user.
Summing up the state of the art, dispensing systems are known which primarily permit individual doses to be dispensed and in a few cases multiple doses. In systems permitting a single dose, the release of detergent is generally operated on the basis of a delayed release, which may be triggered by means of a rise in temperature, an increase in pressure or centrifugal forces, for example. What systems permitting multiple doses have in common is that the release is mechanically triggered (valve, piston, gate, etc.), either on the basis of a command issued by the washing program of the machine or by direct operation on the part of the user.
An underlying objective of the invention is to propose an apparatus for holding and dispensing doses of at least one active composition into a washing machine, a laundry dryer or a dishwasher. The apparatus enables more than one dose to be dispensed (in either one or more laundry washing, drying or dishwasher rinse cycles) and is triggered independently of the commands of an operating program in the machine or intervention by the user.
This objective is achieved by the invention in that at least two separate compartments are provided for respectively receiving and dispensing at least one active composition. An opening mechanism is provided for the compartments, which is operated by means that are activated by conditions prevailing in the interior of the machine, which occur exclusively during a laundry washing, drying or dish-washing cycle. For this purpose, the position of the opening mechanism and/or the compartment(s) relative to one another is altered after at least one respective compartment has been emptied, thereby enabling at least one other respective compartment to be opened by the opening mechanism when activated again.
A preferred embodiment is wherein a first bellows; a second bellows; a connecting pipe with a one-way valve which connects the two bellows to one another; and a hydraulic fluid which is released from the first bellows into the second bellows causing the latter to expand. The opening mechanism is connected to the second bellows in such a way that it is raised due to the expansion of the second bellows, the opening mechanism being so designed that its lifting action causes the compartment(s) to open to the degree that the compartment contents can be substantially entirely dispensed into the machine. This embodiment also includes means which enable the hydraulic fluid gradually to leave the second bellows and a return mechanism connected to the opening mechanism, which enables the opening mechanism to be repositioned as the hydraulic fluid gradually leaves the second bellows, the opening mechanism being guided into a position such that, when activated again, the or other compartment(s) can be opened in the same manner.
In accordance with the invention, the release of hydraulic fluid from the first bellows to the second bellows is operated, directly or indirectly, by rotation of the apparatus with the washing machine or dryer drum. In one especially preferred embodiment of the invention, as the apparatus is rotated with the washing machine or dryer drum, a pivotably secured weight compresses the first bellows, causing the hydraulic fluid to be released to the second bellows. In an alternative embodiment of the invention, the hydraulic fluid is released from the first bellows to the second bellows due to the wet laundry or dry laundry compressing the first bellows directly or indirectly.
Another embodiment of the invention is characterized in that the opening mechanism is raised, directly or indirectly, by means which are altered in form, at least to a certain degree, when the temperature is increased, until at least one compartment has been opened wide enough for the compartment contents to be essentially entirely released into the machine. The means undergo the reverse change of form, at least to a certain degree, on cooling, so that the opening mechanism is guided into a position from which the or other compartment(s) can be opened in the same manner when activated again.
An alternative to this embodiment of the invention is characterized by a rigid compartment with a material disposed therein, which expands as the temperature increases and shrinks on cooling, in particular a wax. Preferably, the opening mechanism is raised by means of a flexible diaphragm, which responds to the expansion of the material. Another alternative to the embodiment of this invention which reacts to the effect of temperature is wherein a bimetallic strip, which bends when the temperature increases and returns to shape on cooling.
Particularly preferably, the opening mechanism is guided into its new position by means of a key groove and a nose co-operating therewith. The opening mechanism preferably has at least one blade or a tongue.
In one particularly practical arrangement, the apparatus is firmly but detachably secured in the interior of the machine. Preferably, the apparatus comprises a cartridge with four to fifteen, more preferably ten, compartments, the compartments preferably being laid out in a circular arrangement in the cartridge.